Columbus, OH has a web page allowing you to sign up to receive SMS alerts for Greenway Trail closings, hazards and construction information. I get something once or twice a month, usually construction or high water warnings.

Just got this:

Due to a large tree falling on the Alum Creek Trail, a section North of Innis and South of the Easton Soccer fields will be closed until further notice.

Fortunately it's not on the way home.